How to Spell on a Calculator? The Classic Number Trick from School
If you've ever sat in a math class (or, let's be honest, any class where calculators were allowed), secretly typing in numbers only to flip your calculator over and watch a word appear, then you were part of the elite. But do you still know how to spell on a calculator?
What makes the words displayed by calculators so fascinating is that they are ambigrams, meaning you can read the symbols in multiple directions. To read a word, you enter the numbers that resemble its letters reversed, then turn the calculator upside down. Suddenly, a 7 becomes an L, a 3 an E, and a simple mathematical tool becomes capable of spelling words, just so you can amuse your classmates.
If you enjoy this kind of hidden language, you might also love exploring our leet-speak translator as well as our related article: What is 1337: The Elite Language Explained.
💡 Did you know?
Calculator spelling is also known as beghilosz, named after the only letters that you can form on a calculator with a 7-segment display: b, e, g, h, i, l, o, s, and z.
In this article, you'll learn or rediscover:
- How to write things on a calculator;
- How to write "hello" on a calculator;
- How to write "I love you" on a calculator; and
- Plenty of fun words you can spell on a calculator you might have forgotten.
So grab your old calculator, turn it upside down, and get ready to relive one of the simplest and funniest school tricks ever invented.
🔎 The earliest known example of writing on a calculator dates back to the 1970s, with the number 5318008. We'll let you type it in and turn your calculator over to discover why it became such a cheeky classic among students everywhere.
Whether you're here to refresh your memory of calculator spelling or discover it for the very first time, you're in the right place. Let's start with the basics.
To understand how to spell on a calculator, you first need to know a simple trick: on calculators with a 7-segment display, some numbers appear to resemble letters when viewed upside down. By matching each number to its corresponding letter, you can create a limited, but functional, subset of the alphabet:
Here's the basic version most people remember from their school days:
Digit | Letter |
|---|---|
0 | O |
1 | i or l |
2 | Z |
3 | E |
4 | h |
5 | S |
6 | G |
7 | L |
8 | B |
9 | g |
Pretty cool, right? You now know how to spell on a calculator just by using these number-to-letter substitutions and flipping it upside down! If you'd like to dive deeper into this topic, check out our article What Letters Look Like Numbers.
Please note that not every calculator is compatible with this trick. The best ones are those with 7-segment liquid crystal (LCD), fluorescent, LED, or Panaplex displays. Modern models with matrix screens and displays with 14 or 16 segments, specially designed to display most characters, make this trick kind of obsolete.
Some calculators even change the game a bit; for instance, older models sometimes omit the base of 6 and 9, making them resemble lowercase "q" and "b". Other variants of the alphabet match 0 to D instead of "o", 6 to the lowercase "g", and 9 to "a" or "@".
Writing sideways
If you rotate your calculator 90° counter-clockwise, you create a different set of characters:
Digit | Letter |
|---|---|
0 | O |
1 | — |
2 | N |
3 | M |
4 | J |
5 | u |
6 | b |
7 | C |
8 | ∞ |
9 | a |
Flip it the other way (90° clockwise) and you'll get yet another set of characters:
Digit | Letter |
|---|---|
0 | O |
1 | — |
2 | N |
3 | W |
4 | r |
5 | n |
6 | a |
7 | J |
8 | ∞ |
9 | b |
Thus, depending on your calculator and the angle at which you hold it, you can write entire words simply by combining numbers and imagination.
💡 Tip
If your calculator has a hexadecimal mode, try it out! This mode lets you use the letters A to F, giving you more options for spelling words (and you don't even need to flip your calculator upside down). Many Casio and Texas Instruments models include this mode.
What makes words you can spell on a calculator so much fun is realizing just how many you can create by simply turning this ordinary tool upside down.
Here are some classic examples of words formed with a calculator:
Word | Number |
|---|---|
hi | 14 |
hello | 07734 |
giggle | 376616 |
hill | 7714 |
goose | 35006 |
shoes | 53045 |
be | 38 |
bees | 5338 |
solo | 0705 |
gig | 616 |
boil | 7108 |
Can you find the longest possible word using only the letters on your calculator? The current record, among calculator enthusiasts, is "eggshell" (77345663), but perhaps you can beat it!
That's it, you're all set! You now know (or have just rediscovered) how to write words on a calculator. It's time to find your old calculator and impress your friends (or your kids) with your newly (re)discovered skills!
553580. Contrary to what one might think, "obsess" is one of the easiest words to spell on a calculator — Here's how:
- Type 553580.
- Turn the calculator upside down.
- That's it, "obsess" appears on your calculator with 0 = O, 8 = B, 5 = S, 3 = E.
On a standard seven-segment calculator, it's impossible to write "I love you" exactly, as there isn't a reversed equivalent for the letters V, Y, and U. Back when pagers were in use, people used the code "143" to show their love. The numbers correspond to the number of letters in each word: 1 for "I", 4 for "love", and 3 for "you". This clever abbreviation actually originates from Morse code.
This article was written by Claudia Herambourg and reviewed by Steven Wooding.